Self-assembly, a fundamental process at all scales, plays a vital rule in biology and provides an important guidance for design and fabrication of functional materials. Particularly, self-assembly provides an attractive and practical methodology for creating artificial nanostructures that promise broad impacts and applications in the emerging field of nanoscience: for examples, self-assembled nanoparticles may lead to novel optical materials and high density magnetic recording media; the self-assembled monolayers have enabled nanometer thickness organic films to be constructed on a variety of substrates for modeling biological surface to control the fate of cells, building molecular electronic devices, developing nanolithography, and generating nanostructures for biomedical diagnostics. The self-assembly of oligopeptides and other organic molecules has resulted in nanofibers as the functional matrices of hydrogels that are useful for tissue engineering, inhibitor screening, and wound healing. Although these works reflect exciting and important development of self-assembled nanostructures in extracellular settings or a non-biological arena, intracellular creation of artificial nanostructures remains unexplored and its subsequent biological effects unknown despite of its significances and potential applications.
Exploring intracellular artificial nanostructures is significant for several reasons. First, self-assembled nanostructures such as cell membranes, strands of nucleic acids, and actin filaments, prevail in living cells and are indispensable for critical cellular functions (i.e., as structural motifs for maintaining integrity of cells, as effective storages for keeping genetic information, and as active devices for regulating numerous of cellular processes), therefore intracellular artificial nanostructures provide an attractive and effective strategy from perturbing the cellular activities to managing the behaviors of cells. Second, many diseases are related to mishaps in cellular nanostructures (i. e., mismatch of base pairs, formation of β-amyloid, and misfolding of proteins), and hence intracellular artificial nanostructures offers a versatile platform for mimicking, modeling, and understanding the mechanism of diseases, thereby developing the therapeutic approaches. Third, great advances in molecular cell biology, such as the study of biological process at the molecular level, during the last five decades have led to new insights into the evolution of life form, and now there is a need to correlate biological process beyond molecule level and to understand structure and dynamics as a system (i.e., system biology). Self-assembled intracellular artificial structures at nanoscale would lend a convenient means to examine the structure and dynamics of cellular and organismal function and to allow previously unconnected domains of knowledge to be understood at new levels of complexity.
Because nanostructures created in situ within live cells have wide potential applications as discussed in the above, there is a need for a convenient method to create intracellular artificial nanostructures.